Interocclusal appliance and method

ABSTRACT

An interocclusal appliance is formed from a single polymer material composition as one unitary piece or from multiple polymer material compositions as a two-piece preform. The two-piece preform includes a base material and an impression material that has a softening point lower than the base material. Teeth are received into the heat-softened impression material, so as to contour the impression material. A portion of the impression material also may contour to a portion of the user&#39;s palate. In certain embodiments, substantially no polymeric material contacts the front surfaces of the front teeth, leading to greater comfort and better air flow between front teeth. In still another embodiment, the appliance fits over front teeth only and no polymeric material contacts the maxillary molars.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to interocclusal appliances worn in the mouth toprevent tooth structure loss resulting from subconscious parafunctionalmandibular habits known as bruxism or clenching.

2. Description of the Prior Art

Bruxism has been found to be a major factor in occlusal tooth surfacewear, and may be a significant potential risk factor for dental implantfailure. Interocclusal appliances, such as mouth guards or nightguards,have been recognized as beneficial to alleviate the adverse effects ofbruxism and clenching.

Prior interocclusal appliances include those that are fitted by a dentalprofessional and those that are self-fitted. Professionally fittedinterocclusal appliances are molded of relatively hard acrylic resinfrom casts of the patient's mouth taken from a dental impression. Thisprocedure requires multiple visits to the dental professional's office,and thus is time-consuming and expensive.

Self-fitted interocclusal appliances typically include a thermoplasticchannel or trough in the shape of a maxillary arch. A thermoplasticimpressionable liner material is carried in the trough. Suchthermoplastic impressionable liner material has a softening point lowerthan that of the trough. The liner is softened by immersing it in hotwater. Then, the liner is molded to conform to a user's mount/teeth byinserting the heated liner into the user's mouth, placing it against themaxillary arch. The user's jaw is closed and biting pressure is appliedto force the maxillary teeth into the liner. Representative self-fittedinterocclusal appliances of this type are shown in U.S. Pat. Nos.5,566,684; 6,302,110; and 6,820,623; and European Patent Application No.EP 0 359 135 A1.

Problems were encountered with these prior self-fitting nightguards.Home users had some difficulty fitting the appliance to their own teeth.It can be difficult to properly center and align (register) the heatedimpressionable liner material of the nightguard relative to one's ownmaxillary arch. If the fit is not proper, the user could experiencediscomfort on wearing the nightguard and/or the nightguard couldprematurely wear out. In addition, in some prior nightguards, thethermoplastic impressionable liner material was used without a backingplate. Upon severe bruxing or clenching, many users would bite throughthis material, thus wearing out the appliance and losing the benefit ofprotecting teeth surfaces. In other prior nightguards, the thermoplasticimpressionable liner material separated from the trough as a result ofshearing forces from a user's severe bruxing or clenching.

U.S. Pat. No. 6,830,051 illustrates an improved self-fittinginterocclusal appliance that includes an impression material unitarilymolded to a base material, creating a high shear resistance bond betweencomponents. In this prior appliance, the lower base has the shape of amaxillary dental arch. An impression preform of a softenablethermoplastic is molded to the lower base. The inner side walls of theappliance may be tapered inwardly to facilitate proper placement of theappliance in the user's mouth over the user's upper teeth. Thisappliance thus fits over all upper teeth of the maxillary arch.

Many of the prior self fitting interocclusal appliances includethermoplastic material over all upper teeth of the maxillary arch,including molars and front teeth (incisors and eye teeth). Plasticmaterial between the front lip and front teeth can be uncomfortable.Moreover, when such an appliance is worn, no space or yap is leftbetween the top and bottom teeth. For example, a person's natural bitewould generally leave a gap between the upper incisors and the lowerincisors. The lack of this gap can lead to breathing difficulties forusers accustomed to more mouth breathing at night, such as users whohave frequent nasal congestion. An appliance that does not cover or doesnot substantially cover front teeth, particularly the incisors, would bemore comfortable. In addition, when circumstances permit, an appliancethat permits greater air flow between upper and lower front teeth wouldbe more comfortable.

For some users, the excess material in an appliance extending over theback molars and/or between the back molars and the cheeks is notcomfortable. Such users seek an appliance that satisfactorily protectsteeth surfaces without covering all teeth of the maxillary arch. Thus,another alternative appliance with such characteristic would be morecomfortable for these users.

SUMMARY OF INVENTION

In a first embodiment of the invention, a one-piece interocclusalappliance for fitting over maxillary teeth of a user is fabricated froma polymeric material formed in a configuration generally of a dentalarch having a bottom plan surface and having two end portions and acentral portion together forming said dental arch. The end portions eachdefine receiving portions for receiving at least one maxillary molar,and the central portion is shaped so as to be disposed behind at leastsome of the user's front teeth. In this embodiment the interocclusalappliance lacks substantial material in front of the user's front teeth.To facilitate fitting, the end portions of the dental arch may be spacedfurther from one another by flexing the polymeric material. Theappliance may be heat and fit, such as by heating the polymeric materialto a temperature that is above its Vicat softening temperature so thatthe receiving portions may be molded into cavities for receiving themaxillary molars, and the central portion may be shaped to conform to aportion of the user's palate behind one or more of the user's frontteeth. Once fitted, the appliance is maintained in fitted position inthe user's mouth over the user's maxillary molars until the user electsto remove said appliance from the mouth.

Certain features may be included to help locate the appliance in theuser's mouth during fitting. For example, the central portion mayinclude a preformed upstanding bridge or arch between the end portions.In addition, a slanted ledge may be formed at the central portion. Asanother example, a front tooth guide may extend generally upwardly froma top surface of the dental arch at the central portion. The front toothguide may comprise a continuous or discontinuous arcuate ridge, or aseries of one or more projections. As yet another example, a pilotchannel may be formed in the end portions between inner and outerupstanding ridges that extend generally upwardly from a top surface ofthe dental arch.

The interocclusal appliance may be formed from a polymeric material,such as polymeric materials having Shore A hardness of at least about20, or combinations of such materials. Materials meeting this criteriainclude ethylene methyl acrylate (EMA) copolymers, ethylene vinylacetate (EVA) copolymers, acrylics, high density polyethylenes (HDPE),styrenics (IMPS), acrylonitrile-butadiene-styrene (ABS) copolymers,poly(rnethylmethacrylates) (IM-PMMA), alpha-polyolefins and mixturesthereof. Other FDA-approved polymeric materials may be suitable. Thehardness, strength or color of the material forming the appliance may bealtered by incorporating one or more types of particles, includingnanoparticles, into the polymeric material. Such particles may beincluded to help a user monitor the wear or degradation of the materialforming the appliance.

Another embodiment of an interocclusal appliance for fitting overmaxillary or mandibular teeth of a user according to the invention hastwo components, a base and an impression material. The two componentstogether initially comprise a preform that may be fitted and formed intothe interocclusal appliance. The base generally has a top surface and abottom surface, where the bottom plan surface is in a configuration of adental arch having two end portions and a central portion togetherforming said dental arch. Impression material is bonded (such as bymolding or adhering) to the top surface of the base, with saidimpression material defining receiving portions in the end portions ofthe base for receiving one or more molars at each end portion. Theimpression material comprises a polymeric material that has a Vicatsoftening temperature, and said base comprises a polymeric material thatmay have a Vicat softening temperature above that of the impressionmaterial. Upon heating the preform to a temperature that is above theVicat softening temperature of the impression material polymericmaterial, the receiving portions may be molded into cavities forreceiving the molars. For greater user comfort, the interocclusalappliance formed from said preform lacks substantial polymeric materialin front of the user's front teeth. In one alternative embodiment, theappliance lacks polymeric material in contact with the tips of at leastsome of the user's front teeth. In another alternative embodiment, theuser's front teeth are supported by the base with the tips of the user'sfront teeth in contact with a portion of the top surface of the base. Inyet another alternative embodiment, one or more air flow passages areformed through or in the base.

Certain features may be included to help locate the interocclusalappliance formed from the preform in the user's mouth during fitting.For example, the central portion may include a preformed upstandingbridge or arch of impression material between the end portions. Inaddition, a slanted ledge of impression material may be formed at thecentral portion. As another example, a front tooth guide may extendgenerally upwardly from a top surface of the base at the centralportion. The front tooth guide may comprise a continuous ordiscontinuous arcuate ridge, or a series of one or more projections. Asyet another example, a pilot channel may be formed in the end portionsbetween inner and outer upstanding ridges that extend generally upwardlyfrom a top surface of the dental arch. It is also possible for the topsurface of the base to be concavely dished at the end portions toreceive the impression material and form the pilot channel. Moreover,the end portions of the base may be flexed apart. Notches may be cutinto the impression material (and/or into the base material) betweeneach end portion and the central portion to assist in flexing thepreform.

The interocclusal appliance may have a base with a dental arch of acertain size adapted to fit most adult mouths. However, to accommodateusers with larger teeth or a larger dental arch, the preform may includeexcess impression material bonded at or near the receiving portions inthe end portions of the base such that upon fitting the appliance saidexcess impression material may engage the user's rear teeth that extendbeyond the end portions of the base. Such excess impression materialwill engage the rear teeth that extend beyond the bottom plan surface ofthe base.

The polymeric material forming the base may have a Shore A hardness ofat least about 20. Polymeric material such as ethylene methyl acrylate(EMA) copolymers, acrylics, high density polyethylenes (HDPE), styrenics(IMPS), acrylonitrile-butadiene-styrene (ABS) copolymers, andpoly(methylmethacrylates) (IM-PMMA) may be suitable for forming thebase. Other FDA-approved polymeric materials may be suitable as well.

One or more types of larger or nanoparticles may be added to thepolymeric material forming the base to alter hardness, strength or colorof the material forming the appliance. Representative particles includepigments, colorants, plated clays, carbon fibrils and carbon nanotubes.

Particles to impart opacity or translucency to the polymeric materialforming the base may serve also as a wear indicator for theinterocclusal appliance. As such, a change in color or opacity canevidence that polymeric material is wearing away due to the clenching orbruxing occurring in association with the interocclusal appliance. Whena certain color change or opacity variance is observed, the user maydetermine that the interocclusal appliance is no longer as effective inprotecting his or her teeth.

The impression material may comprise ethylene methyl acrylate (EMA)copolymers, ethylene vinyl acetate (EVA) copolymers, acrylics, highdensity polyethylenes (HDPE), styrenics (IMPS),acrylonitrile-butadiene-styrene (ABS) copolymers,poly(methylmethacrylates) (IM-PMMA), alpha-polyolefins and mixturesthereof. Other FDA-approved polymeric materials may be suitable as well.In one advantageous embodiment, the impression material comprises from 0to 85% by weight of an ethylene vinyl acetate copolymer having up toabout 30% by weight vinyl acetate or mixture of such copolymers, andfrom 15 to 100% by weight of one or more alpha-polyolefins. If anethylene vinyl acetate copolymer of mixture of such copolymers ispresent in the impression material, it may be advantageous to have lessthan about 10% by weight vinyl acetate. Particles, including largerparticles or nanoparticles, may be added to the polymeric materialforming the impression material to alter hardness, strength or color ofthe material forming the appliance.

Some users may prefer an interocclusal appliance that fits over thefront teeth rather than the molars. Such an appliance may be formed froma preform comprising a base and an impression material. The base in suchembodiment has a bottom plan surface in a configuration of a partialdental arch, and the impression material is bonded to the top surface ofsaid base, with said impression material defining a receiving portionfor receiving two or more maxillary front teeth. Just as with the otherembodiments noted above, the impression material has a softeningtemperature lower than the softening temperature of the base so thatwhen the preform is heated the impression material may be softened totake an impression of the user's teeth, such as the front incisors.Preferably, at least six front maxillary teeth are engaged by theimpression material to form the interocclusal appliance.

Another aspect of the invention is a method of fabricating aninterocclusal appliance for alleviating adverse effects of bruxing orclenching events. In a first embodiment of such method, a one componentappliance is formed from a polymeric material having a Shore A hardnessof at least 20. In a second embodiment of such method, the one componentappliance is formed in a configuration generally of a dental arch havinga bottom plan surface and having two end portions and a central portiontogether forming said dental arch. The end portions each definereceiving portions for receiving at least one maxillary molar, and thecentral portion is shaped so as to be disposed behind at least some ofthe user's front teeth. The interocclusal appliance formed in thismethod lacks substantial material in front of the users front teeth. Themethod may further include the steps of heating the polymeric materialto a temperature that is above its Vicat softening temperature andinstalling the appliance into a user's mouth and biting pressure isapplied thereon so that the receiving portions may be molded intocavities for receiving the maxillary molars. Alternatively, the methodmay include the step of installing the appliance into a user's mouth andbiting pressure is applied thereon so that the receiving portions may bemolded into cavities for receiving the maxillary molars, followed bycuring the material to retain the shape of the maxillary molarencasement cavities. The polymeric material selected for such methods isconsistent with those identified for the interocclusal appliancesaccording to the invention as noted earlier.

In particular variations the method may further comprise the step ofindexing the appliance within the user's mouth during the installingstep by locating front teeth in front of a slanted ledge formed at thecentral portion of the dental arch. Or, the method may further comprisethe step of indexing the appliance within the user's mouth during theinstalling step by locating front teeth substantially adjacent to afront tooth guide extending generally upwardly from a top surface of thedental arch at the central portion.

Another alternative method of fabricating an interocclusal appliance foralleviating adverse effects of bruxing or clenching events may compriseforming a two-part preform. The preform has an appliance base of apolymeric material having a Shore A hardness of at least about 20, andan impression material bonded to such base. The impression material mayhave a Vicat softening temperature lower than the Vicat softeningtemperature of the material comprising the base. The polymeric materialof the appliance base may be ethylene methyl acrylate (EMA) copolymers,acrylics, high density polyethylenes (HDPE), styrenics (IMPS),acrylonitrile-butadiene-styrene (ABS) copolymers, andpoly(methylmethacrylates) (IM-PMMA), and mixtures. In one variation theimpression material is a polymeric material composition comprising from0 to 85% by weight of an ethylene vinyl acetate copolymer having up toapproximately 30% by weight vinyl acetate, and from 15 to 100% by weightof alpha-polyolefins. Alternatively, the impression material comprisesno more than about 25% by weight vinyl acetate. The impression materialmay consist solely of alpha-polyolefins without ethylene vinyl acetatecopolymers.

The polymeric material comprising the base may contain one or morelarger particles or nanoparticles, such as for example pigments,colorants, plated clays, carbon fibrils and carbon nanotubes. Thepolymeric material comprising the impression material may contain one ormore larger particles or nanoparticles as well.

The Shore A hardness of the base material may range between about 20 andabout 80. The Shore A hardness of the base material may exceed 80.

In another embodiment of this method, the base may be formed in aconfiguration generally of a dental arch having a bottom plan surfaceand having two end portions and a central portion together forming saiddental arch. The central portion may be shaped so as to be disposedbehind at least some of the user's front teeth. The impression materialis bonded to the top surface of the base, and the impression materialdefines receiving portions in the end portions of the base for receivingone or more molars at each end portion. The appliance formed from saidbase and impression material lacks substantial polymeric material infront of the user's front teeth. The method may further comprise thesteps of heating the impression material to a temperature that is aboveits Vicat softening temperature; and installing the appliance into auser's mouth and applying biting pressure thereon so that the receivingportions may be molded into cavities for receiving the maxillary molars.

In particular variations the method may further comprise the step ofindexing the preform within the user's mouth during the installing stepby locating front teeth in front of a slanted ledge formed at thecentral portion of the dental arch. Or, the method may further comprisethe step of indexing the preform within the user's mouth during theinstalling step by locating front teeth substantially adjacent to afront tooth guide extending generally upwardly from a top surface of thedental arch at the central portion.

As another variation, excess impression material may be bonded at ornear the receiving portions in the end portion of the base such thatupon fitting the preform said excess impression material may engage theuser's rear teeth that extend beyond the end portions of the base. Theexcess impression material engaging the rear teeth extends beyond thebottom surface of the end portions of the base.

Another method of fabricating an interocclusal appliance for alleviatingadverse effects of bruxing or clenching events, comprises the steps offorming an appliance base from a polymeric material having a Shore Ahardness of at least about 20; and bonding to the base an impressionmaterial of a polymeric material composition comprising an ethylenevinyl acetate copolymer having from 0 to 25% by weight vinyl acetate. Asone alternative to this method, the Shore A hardness is at least about80.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a preform for an interocclusal applianceaccording to a first embodiment of the invention;

FIG. 2 is a front elevational view of the preform of FIG. 1;

FIG. 3 is a side elevational view of the preform of FIG. 1;

FIG. 4 is a right side elevational view in partial cross section, takenalong line 4-4 in FIG. 1, showing the interocclusal appliance formedfrom the preform of the first embodiment fitted within in a user'smouth, with the front incisor tooth extending over the buccal peripheralwall of the appliance;

FIG. 5 is a is a top plan view of a preform of an interocclusalappliance according to a second embodiment of the invention;

FIG. 6 is a front elevational view of the preform of FIG. 5, showing thepalate arch provided in such preform;

FIG. 7 is a right side elevational view of the preform of FIG. 5;

FIG. 8 is a cross-sectional view taken along line 8-8 of FIG. 5;

FIG. 9 is a top plan view of a preform of an interocclusal applianceaccording to a third embodiment of the invention;

FIG. 10 is a front elevational view of the interocclusal applianceformed from the preform of FIG. 9 that is fitted into a user's mouth,with the upper teeth and mouth cavity shown in phantom outline;

FIG. 11 is a right side elevational view of the interocclusal applianceformed from the preform of FIG. 9 fitted into a user's mouth, showing anincisor tooth extending over the buccal peripheral wall of the applianceand supported on a front ledge;

FIG. 12 is a cross-sectional view of the preform taken along line 12-12of FIG. 9;

FIG. 12A is a front elevational view in partial cross section of amodified interocclusal appliance formed of one material and having alingual peripheral wall, but lacking the buccal peripheral walls shownin the embodiment of FIG. 9;

FIG. 13 is top plan view of a preform of an interocclusal applianceaccording to a fourth embodiment of the invention;

FIG. 14 is a front elevational view of the preform of FIG. 13;

FIG. 15 is a bottom plan view of the preform of FIG. 13;

FIG. 16 is a right side elevational view of the preform of FIG. 13;

FIG. 17 is a top plan view of the interocclusal appliance formed fromthe preform of FIG. 13;

FIG. 18 is a front elevational view of the interocclusal appliance ofFIG. 17;

FIG. 19 is a right side elevational view of the interocclusal applianceof FIG. 17;

FIG. 20 is a top plan view of a preform of a fifth embodiment of aninterocclusal appliance according to the invention;

FIG. 21 is a front elevational view of the preform of FIG. 20;

FIG. 22 is a left side elevational view of the preform of FIG. 20;

FIG. 23 is a bottom view of the preform of FIG. 20,

FIG. 24 is a cross-sectional view taken along line 24-24 of FIG. 20;

FIG. 25 is a top plan view of the fifth embodiment of an interocclusalappliance formed from the preform of FIG. 20;

FIG. 26 is a front elevational view of the interocclusal appliance ofFIG. 25;

FIG. 27 is perspective view of a preform for a sixth embodiment of aninterocclusal appliance according to the invention;

FIG. 28 is a perspective view of a preform for a seventh embodiment ofan interocclusal appliance according to the invention;

FIG. 29 is a perspective view of a preform for an eighth embodiment ofan interocclusal appliance according to the invention;

FIG. 30 is a front elevational view of the preform of FIG. 29;

FIG. 31 is a top plan view of the preform of FIG. 29;

FIG. 32 is a left side elevational view of the preform of FIG. 29;

FIG. 33 is a cross sectional view of an alternative construction of abase with impression material of a preform for an interocclusalappliance in which the base lacks buccal and lingual peripheral sidewalls and the impression material contacts the top surface of the base;

FIG. 34 is a cross-sectional view of an alternative construction of abase with impression material of a preform for an interocclusalappliance in which the base has a concavely curved top surface and theimpression material contacts the top surface of the base;

FIG. 35 is a cross-sectional view of the preform of FIG. 31, which has abase having buccal and lingual peripheral side walls and a top surfaceand impression material is held on the top surface in the space betweenthe side walls; and

FIG. 36 is a front elevational view of a modification to the eighthembodiment of the interocclucal appliance according to the inventionwhich incorporates breathing enhancing bores.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to FIGS. 1-3, a first embodiment of a preform 10 for aninterocclusal appliance 42 is shown. The preform 10 has a base 12 orbite plate with a top surface and a bottom surface. An impressionmaterial 14 is bonded or adhered onto the top surface of the base 12.One preferred bonding is by molding the impression material over thebase. The base 12 may be formed by injection molding a thermoplasticresin into a base mold cavity, and this base 12 is then placed into anocclusal appliance mold cavity. The impression material 14 may beinjected into the occlusal appliance mold cavity over the base 12. Themold bond between the base 12 and the impression material 14 (whichlater is transformed into the maxillary encasement) is required towithstand the lateral and compressive stresses encountered duringbruxing or clenching at oral cavity temperatures.

The base 12 is in the form of a maxillary dental arch, having an endportion 16 at one terminus of said arch and another end portion 18 atthe other terminus of said arch. Between the two end portions 16, 18 isa central portion 20 of the base. Preferably, and the bottom surface (orocclusal face) of the base is generally planar. The buccal sidewalls ofthe base 12 may slope downwardly from the rear of the preform 10 to thelabial face at the central portion 20 as shown in FIG. 3. The thicknessof the base material may range from about 0.25 mm to about 4.0 mm.

The impression material 14 generally covers the top surface of the base12. The impression material 14 is formed to have a first outerupstanding ridge 22 and a second outer upstanding ridge 24, and an innerupstanding ridge 26. Optionally, a step 28 is formed in the innerupstanding ridge 26 such that the inner upstanding ridge of impressionmaterial at the central portion 20 of the base is higher than the innerupstanding ridge of impression material formed at the end portions 16,18 of the base 12. The upper surfaces of the impression material betweenthe outer upstanding ridges 22, 24 (buccal peripheral walls) and theinner upstanding ridge 26 (lingual peripheral wall) define toothreceiving portions 30, 32. Tooth receiving portions 30, 32 mayalternately be called pilot channels configured to facilitate placementof the user's maxillary molars at an optimal position during andthroughout self-fitting of the appliance. The front face 34 of the innerupstanding ridge 26 is sloped downwardly, at an angle complementary tothe angle at which upper or maxillary front incisor and/or bicuspidteeth generally are disposed in an adult mouth. The impression material14 is transformed into a maxillary molar encasement during self-fittingof the interocclusal appliance 42 (FIG. 4). Preferably, to secure adesired maxillary molar encasement, about 3.5 g to about 7.0 g ofimpression material covers the base material. However, more or lessimpression material may be used to form the preform as desired.

An interocclusal appliance 42 (FIG. 4) of a first embodiment of theinvention is formed from the preform 10 of FIGS. 1-3. The preform 10 isheated, such as by immersion in boiling water for 30 seconds to 2minutes to soften the impression material 14. The preform 10 is heatedto a temperature that can be comfortably withstood by oral tissue (e.g.,preferably below about 140° F.). The preform 10 is then inserted intothe mouth (oral cavity) with the upper molars (maxillary occlusalsurfaces) seated in the teeth receiving portions 30, 32 of the preform10. Biting pressure is applied and the maxillary molars are impressedinto the impression material 14. The impression material flows over andaround the molars to adapt to the shape of the surfaces of the maxillarymolars. Upon cooling, the impression material 14 is transformed into areusable flexible maxillary molar encasement within the appliance 42.

Alternatively, depending upon polymeric material selected as theimpression material, the interocclusal appliance 42 may be fitted firstand then heated to set the polymeric material. In this case, beforeheating, preform 10 is inserted into the mouth (oral cavity) with theupper molars (maxillary occlusal surfaces) seated in the teeth receivingportions 30, 32. Biting pressure is applied and the maxillary molars areimpressed into the impression material 14. The preform 10 is thenheated, such as by immersion in boiling water for a desired time so asto set the polymeric material into a reusable flexible maxillary molarencasement within the appliance 42.

Referring back to FIG. 1, fitting of the preform 10 is simplified wherethe preform 10 flexes. By flexing it is meant that the end portions 16,18 can be separated from one another a greater distance by urging endportion 18 away from end portion 16. Thus, as shown in FIG. 1, endportions 16, 18 are separated from one another initially by a firstdistance, which can be represented by the distance L1 from center lineC. Upon flexing, end portions 16, 18 are separated from one another by asecond distance, which is represented in FIG. 1 by the distance L2 fromthe center line C, where L2 is greater than L1. For example, the rangeof flex distance (L2-L1) may be from about 2 to 35 mm. Even though thematerial selected for the base 12 is not expected to be softened uponheating during the fitting procedure, the configuration of the preform10 with a base central portion 20 narrower in width than the widths ofthe end portions 16, 18 permits greater flexing and correspondinglygreater ease when fitting the appliance over maxillary molars.

While the impression material 14 in the teeth receiving portions 30, 32adapts to the shape of the surfaces of the maxillary molars, theupstanding ridge 26 may be lengthened and fitted to the user's palatetissue extending behind the front teeth. Referring to FIG. 4, theappliance 42 has been fitted in a mouth 38 so that the upstanding ridgeof the preform is stretched and thinned to form a flap or palate moldedsurface 44. Thus, although FIG. 4 is identified as a partialcross-section of the preform in FIG. 1, more accurately, it is a partialcross-section of the appliance 42 formed from the preform of FIG. 1. Theimpression material forming the front portion of the upstanding ridge 26including the step 28 in such ridge 26 has been shaped to conform to theuser's palate and to support the user's front teeth when the appliance42 is worn.

FIG. 4 also shows that the interocclusal appliance 42 fits in the user'smouth 38 such that the sloped front face 34 of the preform 10 nowcontacts the back surface of the user's front teeth 40. No impressionmaterial 14 contacts the front surface of the user's front teeth. Noimpression material extends between the front teeth and the user's upperlip. No impression material and no base material extend below the lowertip of the user's front teeth. As so fitted, the interocclusal applianceleaves a more natural gap between a user's front incisor teeth. Such gapor air channel permits the user to breathe more naturally through his orher mouth during sleep.

For embodiments in which the impression material is heated beforefitting to the teeth, rheological characteristics of the base polymericmaterial (often a thermoplastic material, but may be a thermosetmaterial) include a Vicat softening temperature (ASTM D1525) of at least65° C., which is well above the temperatures reached during the fittingprocedure, and a Shore A hardness of at least about 20. One range forShore A hardness for base materials is from about 20 to about 80 (e.g.,19 to 78). The polymeric material selected for the base has a softeningtemperature sufficiently above that of the polymeric material selectedfor the impression material such that the thickness of the base is notsignificantly reduced as a result of compressive forces during fitting.The base material must not be toxic to humans when incorporated into aninterocclusal appliance for oral use.

Polymeric materials, including resins, meeting these criteria include,but are not limited to, ethylene methyl acrylate (EMA) copolymers,acrylics, high density polyethylenes (HDPE), styrenics (IMPS),acrylonitrile-butadiene-styrene (ABS) copolymers,poly(methylmethacrylates) (IM-PMMA), polypropylene, polycarbonate,polycaprolactam, polycaprolactone, polyurethanes, polyesters,polypropylene ethylene propylene diene monomer (PP/EPDM), thermoplasticvulcanizates (TPV), acrylic rubber TPV, styrene-butadiene-styrene (SBS)TPV, low density polyethylene (LDPE), polyvinyichoride (PVC), very lowdensity polyethylene (VLDPE), styrene-butadiene copolymer (SBC)elastomer compounds, styrene-butadiene-styrene (SBS) linear blockcopolymers, styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS)polyethersulfone (PES), glass reinforced polyethersulfone,polyphenylsulfone (PPSU), styrene-acrylonitrile (SAN),acrylic-styrene-methyimethacrylate coploymers (NAS),polydimethylsilicone (PDMS), polyurea, silicone-polyurea, segmentedpolyurethane (SPU), perfluoroelastomer (FFKM), perfluoroelastomer(FEPM), chlorosulfonated polyethylene rubber, fluoroelastomer, siliconeroom temperature vulcanizate (RTV), cast polyurethane, chloroprenerubber, hydrogenated nitrile-butadiene rubber (HNBR), nitrile rubber,silicone rubber, perfuoroelastomer compounds (FFKT), and mixturesthereof.

An exemplary thermoplastic material suitable for the base is an ethylenemethyl acrylate (EMA) copolymer available from DuPont under thetrademark ELVALOY®1609 AC. This EMA copolymer contains approximately 9%by weight acrylate and has a Vicat softening temperature of 70° C., anda Shore A hardness of 97. Another thermoplastic material that may beused for the base is ELVALOY® EMA copolymer blended with ELVAX® EVAethylene vinyl acetate copolymer or with PELLETHANE® TPU elastomer, suchas in proportion ranging between 10% to 50% PELLETHANE TPU by weight.PELLETHANE® 2103-80 AEN is a thermoplastic polyurethane elastomeravailable from Dow Chemical Co. Yet another thermoplastic material thatmay be used for the base is ELVAX 750 EVA blended with LLDPE or LDPEwith the LLDPE or LDPE content ranging from 25% to 90% by weight.

Other exemplary thermoplastic materials suitable for the base are CyroAcrlitei SuPure M30 acrylic available from Cyro Industries, Nova Sclair2908 high density polyethylene (HDPE) available from Nova Chemicals,Nova Chemicals NAS 30 Series High Performance Styrenic, and BASF Terlux2812 acrylonitrile-butadiene-styrene copolymer. Table 1 below identifiescharacteristics of certain of these exemplary polymeric materials. Suchmaterials are indicated as FDA-approved for oral use.

TABLE 1 Property Flex Notched Linear Polymer Mod Durometer, Izod FDAShrink Bottom Material (Gpa) D, M, R (J/cm) Haze % 21 CFR (cm/cm)Elvaloy 1609 0.80 46 D NV- NV- Yes NV Med Med 177.1520(b) Acrylic 3-3.390-94 M 0.25 1.0 Yes NV High Density 0.80- 55-69 D 0.2-0.8 NV- Yes NVPolyethylene (HDPE) 1.28 60 R High 177.1520(c) <55M 2.2 Poly(propylene)(h-PP, 1.37 108 R 0.3  NV- Yes co-PP) High Styrenics (IMPS, PS) 2-3.370-74 M 0.2-1.27 0.6- Yes 0.002- 1.0 Class VI 0.006 Polyesters (PET,PBT) 1.7- 72-93 M 0.27-NB NV- Yes 4.1 Low Injection Molded 2.6-3.1 68-89M 0.12-0.3 1-2 Yes 0.002- Poly(methylmethacrylate) 177.1010; 0.006(PMMA, IM-PMMA) 180.22; 1580 Poly(carbonate) (PC) 1.8- 65 M 16-21 1-2Yes 4.1 118 R Poly(caprolactam) Nylon 0.1-3.2 55-88 M 0.7-NB NV- Yes 6High Acrylonitrile-butadiene- 2.65 60 M 1.25 NV- Yes 0.4-0.7 styreneco-polymer (ABS) Med Class IV (in/in) NV = No value NB = No break

Suitable polymeric materials for the impression material 14 includethermosetting and thermoplastic polymer resins. Potential polymericmaterials for the impression material include ethylene methyl acrylate(EMA) copolymers, ethylene vinyl acetate (EVA) copolymers, acrylics,high density polyethylenes (HDPE), styrenics (IMPS),acrylonitrile-butadiene-styrene (ABS) copolymers,poly(methylmethacrylates) (IM-PMMA), alpha-polyolefins, polypropyleneethylene propylene diene monomer (PP/EPDM) thermoplastic vulcanizates(TPV), acrylic rubber TPV, styrene-butadiene-styrene (SBS) TPV, lowdensity polyethylene (LDPE), polyvinylchoride (PVC), styrene-butadienecopolymer (SBC) elastomer compounds, styrene-butadiene-styrene (SBS)linear block copolymers, styrene-isoprene-styrene (SIS) linear blockcopolymers, styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),styrene-acrylonitrile (SAN), polydimethylsilicone (PDMS), polyurea,silicone-polyurea, segmented polyurethanes (SPU), perfluoroelastomer(FFKM), perfluoroelastomer (FEPM), chlorosulfonated polyethylene rubber,fluoroelastomer, silicone room temperature vulcanizate (RTV), castpolyurethane, chloroprene rubber, hydrogenated nitrile-butadiene rubber(HNBR), nitrile rubber, silicone rubber, perfuoroelastomer compounds(FFKT), and mixtures thereof.

Such polymeric materials for the impression material may include anethylene vinyl acetate (EVA) copolymer available from DuPont under thetrademark ELVAX® having a vinyl acetate content of at least 25%. Onepreferred EVA copolymer is ELVAX® 150 having a 33% vinyl acetate contentby weight, a Vicat softening temperature of 36° C., and a Shore Ahardness of 73. Alternatively, the impression material may be analpha-polyolefin, such as EXACT 4006 available from ExxonMobil, ENGAGE8407 and ENGAGE 8842 available from Dow Chemical or AFFINITY EG 8200Gavailable from Dow Chemical. The polymeric material for the impressionmaterial may be a mixture of resins, such as from 10 to 100% by weightalpha-polyolefin with from 0 to 90% by weight of an ethylene vinylacetate copolymer having up to about 30% by weight vinyl acetate.Alternatively, such mixture may be from 15 to 100% by weight alphapolyolefin with from 0 to 85% by weight of an ethylene vinyl acetatecopolymer having up to about 30% by weight vinyl acetate. Table 2 belowsets out characteristics of certain of these exemplary polymericmaterials. Such materials are indicated as FDA-approved for oral use.

TABLE 2 Property Vicat Duro- Duro- Polymer- Soften meter meter MeltingFDA Impression Material Pt, C./F. A D Pt, C./F. 21 CFR Elvax 150 36/97 73 24 63/145 177.1350 (a)(1) Exact 4006 43/109 79 20 60/140 175.105(a)(2) Engage 8407 41 72 20 60 177.1520(c) 3.2c Engage 8842 CNA 54 11 38177.1520(c) 3.2c Affinity EG 8200G <45/<113 70 NV 63/145 176.170(c) NV =No value CNA = Can not Ascertain

Particles, including larger particles or nanoparticles may be added tothe polymeric materials forming the base or the impression material. Forexample, colorants (such as pigments known for use with thermoplasticand thermoset resins) may be incorporated into the base or impressionmaterial to improve aesthetics. Colorants may have added benefit toserve as a wear indicator, so that the user can detect when portions ofthe base material are wearing down due to bruxing or clenching after anappliance is worn. As another example, plated clays, carbon fibrilsand/or carbon nanotubes may be added to enhance strength of the basematerial or the impression material.

Referring next to FIGS. 5 to 8, a second embodiment of the inventioncomprises a preform 50 having a base 52 or bite plate with a top surfaceand a bottom surface. An impression material 54 is adhered or bondedonto the top surface of the base 52, such as by co-molding. The base 62has two end portions 56, 58 that are joined by an arch 60 formed betweenthe two end portions 56, 58. Arch 60 curves concavely such that eachbottom tip of said arch meets an end portion the bottom surfaces (orocclusal faces) of the end portions 56, 58 of the base are generallyplanar. The buccal sidewalls of the end portions of the base 12 mayslope downwardly slightly from the rear of the preform 50 toward thefront of the preform as shown in FIG. 7.

By virtue of flexibility of the arch 60 material, the preform 50 may beflexed from a first position where end portions 56, 58 are spaced aparta first distance to a second position where end portions 56, 58 arespaced apart a second distance, where the second distance is greaterthan the first distance. Notches 62, 64 are formed in the base 52 whereeach bottom tip of said arch 60 meets an end portion 56, 58. Notches 62,64 enhance the ability to flex the preform 50 from a first positionwhere end portions 56, 58 are spaced apart a first distance to a secondposition where end portions 56, 58 are spaced apart a second distance,where the second distance is greater than the first distance. Suchflexing is not shown in FIG. 5.

The impression material 54 generally covers the top surface of the base52. The impression material 54 is formed to have a first outerupstanding ridge 66 and a second outer upstanding ridge 68, and an innerupstanding ridge 70 that extends from arch 60. The upper surfaces of theimpression material between the outer upstanding ridges 66, 68 (buccalperipheral walls) and the inner upstanding ridge 70 (lingual peripheralwall) define tooth receiving portions 72, 74. Tooth receiving portions72, 74 may alternately be called pilot channels configured to facilitateplacement of the user's maxillary molars at an optimal position duringand throughout self-fitting of the appliance. The top face of the arch60 is sloped downwardly, at an angle complementary to the angle of apalate in an adult mouth. The impression material 54 at the teethreceiving portions 72, 74 is transformed into a maxillary molarencasement during self-fitting of the interocclusal appliance of thissecond embodiment. In addition, the arch 60, which aids in self-fittingthe interocclusal appliance in the mouth, may be stretched and thinnedto conform to the palate surface behind the front maxillary teeth whenthe impression material 54 is softened for self-fitting the appliance.

A finished appliance according to this second embodiment is not shown inthe Figures. However, just as with the first embodiment shown in FIG. 4,for this second embodiment of interocclusal appliance, no impressionmaterial 54 contacts the front surface of the user's front teeth. Noimpression material extends between the front teeth and the user's upperlip. No impression material and no base material extend below the lowertip of the user's front teeth. The front teeth are supported by theimpression material from behind, but are not encased in impressionmaterial, and thus the interocclusal appliance is more comfortable towear.

FIGS. 9 to 12 show a preform 80 and an interocclusal appliance 110 for athird embodiment of the invention (appliance 110 shown in FIG. 11). Thepreform 80 has a base 82 and impression material 84 molded to a topsurface of such base 82. The base 82 is in the shape of a maxillarydental arch, having end portions 86, 88 and a central portion 90 betweensuch end portions 86, 88. The end portions 86, 88 have upstanding sidewalls 87, 89 and an upstanding lingual wail 91 that extends along thedental arch along the end portions 86, 88 and the central portion 90.The central portion 90 of the base 82 has only the upstanding lingualwall 91, and does not have an upstanding labial or front wall.

The impression material 84 generally covers the top surface of the base82. The impression material 84 is formed to have a first outerupstanding ridge 92 and a second outer upstanding ridge 94, and an innerupstanding ridge 96. Optionally, a step (not shown) may be formed in theinner upstanding ridge 96 such that the inner upstanding ridge ofimpression material at the central portion 90 of the base is higher thanthe inner upstanding ridge of impression material formed at the endportions 86, 88 of the base 82. The upper surfaces of the impressionmaterial between the outer upstanding ridges 92, 94 (buccal peripheralwalls) and the inner upstanding ridge 96 (lingual peripheral wall)define tooth receiving portions 98, 100. Tooth receiving portions 98,100 may alternately be called pilot channels configured to facilitateplacement of the user's maxillary molars at an optimal position duringand throughout self-fitting of the appliance. The front face 102 of theinner upstanding ridge 96 is sloped downwardly, at an anglecomplementary to the angle at which upper or maxillary front incisorand/or bicuspid teeth generally are disposed in an adult mouth. Theimpression material 84 is transformed into a maxillary molar encasementduring self-fitting of the interocclusal appliance 110 (FIG. 11).

While the impression material 84 in the teeth receiving portions 98, 100adapts to the shape of the surfaces of the maxillary molars, theupstanding ridge 96 may be lengthened and fitted to the user's palatetissue extending behind the front teeth 104. Referring to FIG. 11, theappliance 110 has been fitted in a mouth 106 so that the upstandingridge of the preform is stretched and thinned to form a flap or palatemolded surface 112.

FIG. 11 also shows that the interocclusal appliance 110 fits in theuser's mouth 106 such that the sloped front face 102 of the impressionmaterial contacts the back surface of the user's front teeth 104 tosupport those teeth as the appliance is worn. The top surface of thebase 82 contacts the lower tips of the user's front teeth. Asillustrated in FIG. 11, no impression material 84 contacts the frontsurfaces of the user's front teeth. No impression material extendsbetween the front teeth and the user's upper lip. Thus, this thirdembodiment is comparable to the first embodiment shown in FIG. 4, exceptthat base material extends below the lower tips of the user's frontteeth 104 to support those teeth when the appliance is worn. In thismanner, base material or bite plate separates occlusal surfaces of allof the user's teeth, not just the molars.

While the first 10, second 50 and third 80 embodiments of the preformsaccording to the invention have been shown optimally without anyimpression material extending between the front surfaces of the user'sfront teeth and the user's upper lip, some impression material maycontact the user's front teeth in finished appliances within the scopeof the invention. Not all users will have complete sets of front teeth,and not all users will have dental arches that match the span of thedental arch of the preform. Thus, it is intended that appliances formedfrom preforms that do not have substantial impression material extendingin front of a user's front teeth are within the scope of the presentinvention. Unlike prior self-fitted interocclusal appliances, to achievethe comfortable fit desired herein, the appliances according to theinvention are not intended to have substantial impression material orbase material in front of a user's teeth, or in contact with a user'sfront (labial) gum tissue.

A fourth embodiment of a preform 120 for an interocclusal appliance 140(appliance 140 shown in FIGS. 17 to 19) is shown in FIGS. 13 to 16. Thepreform 120 has a first base portion 122 and a second base portion 123.The base portions form bite plates with generally smooth and planarbottom surfaces and with top surfaces designed to receive impressionmaterial. The top surfaces have front edges and rear edges.

Impression material 124 is bonded or attached (such as by molding) tothe top surfaces of the base portions 122, 123. As shown in FIGS. 13 to16, the impression material 124 has a right side molded to the firstbase portion 122 and a left side molded to the second base portion 123.The right and left sides are joined together by a bridge 130 ofimpression material 124. The right side and left side have outerupstanding ridges 132 and inner upstanding ridges 134 defining toothreceiving portions 136 and 138. Bridge 130 is shown in FIGS. 13 and 15as being centrally disposed between base portions 122 and 123. It isalso conceivable that such bridge 130 may be positioned closer to therear edges of the base portions 122, 123. Shifting the location ofbridge 130 of impression material 124 may enhance fitting of theappliance into a user's mouth by making a more comfortable engagementwith the user's palate (as described in more detail below).

For embodiments in which a heat and fit procedure is used, upon heatingpreform 120, impression material 124 is softened. The preform 120 isthen installed in the user's mouth with the maxillary molars in contactwith the tooth receiving portions 136, 138. The softer impressionmaterial forming the bridge 130 in the preform 120 enables the user toflex the first and second base portions 122, 123 closer to or fartherfrom one another during fitting. Upon applying biting pressure,impressions or indentations of left side and right side molars 144, 146are made in the impression material 124. During the fitting procedure,the impression material forming bridge 130 is also softened such thatbridge 130 may be shaped into a palate arch 142 to conform to thecontour of the user's palate. Accordingly, an interocclusal appliance140 (FIGS. 17 to 19) comfortably shapes to fit the bite surfaces of themaxillary molars, with a palate arch 142 to help maintain the appliancein register within the user's mouth. No impression material or basematerial is in contact with the user's front teeth. No impressionmaterial or base material is present between the user's front lip andfront teeth.

Referring next to FIGS. 20 to 24, a fifth embodiment of a preform 150for an interocclusal appliance 160 (appliance 160 shown in FIGS. 25 and26) is shown. The preform 150 has a base 152 to which is bonded oradhered (such as by molding) an impression material 154. The base 152forms an arc shape comparable to the maxillary arch or mandibular archof the front teeth in an adult mouth, with a pair of parallel curvedfront and rear walls and two end walls. The base 152 has a front labialridge 156 upstanding from the top surface of the base. Preferably, thefront labial ridge 156 extends along the entire front wall or labialedge of the base 152. The base 152 has a generally smooth and planarbottom surface for occlusal contact between front teeth.

Impression material 154 is bonded or molded to the top surface of thebase 152. Impression material 154 follows the dental arch contour of thebase 152. The top surface of the impression material 154 comprises toothreceiving portion 158.

When using a heat and fit procedure, an interocclusal appliance 160 isformed upon heating the preform 150 to soften the impression material154 without substantially softening the base material. The preform 150is then inserted into the mouth such that the impression material is incontact with the tips of the user's front teeth. Biting pressure isapplied to imbed either the maxillary front teeth or the mandibularfront teeth into the impression material 154. The front labial ridge 156of the base 152 helps to seat the teeth in proper register during thefitting procedure.

A portion of the impression material 154 takes impression of the user'sfront teeth. Tooth indentations 162 are thus formed in the interocclusalappliance 160 (see FIG. 25). Preferably, impressions or indentations 162are formed for at least six front maxillary teeth, such as incisors andbicuspids. In FIG. 25, the appliance 160 has impressions or indentations162 for eight front teeth.

During the fitting procedure for an appliance to be worn over themaxillary front teeth, the user may shape the impression material 164 ofthe preform 150 to create a lingual lip or palate-contoured raised flap164 that helps to engage the appliance 160 and register it in suitableposition in the user's mouth. The palate contoured raised flap 164 maybe formed by pressing the softened impression material 154 with thetongue or with fingers or thumbs while preform with softened impressionmaterial 154 is held within the mouth.

Concurrently, as the dental impressions or indentations 162 are formedin the impression material 154, the impression material may form araised or upstanding front (labial) lip 166. In this way theinterocclusal appliance 160 contacts the front and rear Surfaces of theuser's front teeth, with the base 152 disposed under the tips of suchteeth.

The interocclusal appliance 160 of FIGS. 25 and 26 is different from theother appliance embodiments described previously herein in that no basematerial or impression material encases the maxillary or mandibularmolars. The appliance 160 separates the upper and lower teeth by spacingapart the front teeth, rather than by spacing apart the back teeth ormolars. Still, such embodiment is more comfortable than priorself-fitting interocclusal appliances because the front teeth (incisorsand bicuspids) are supported at the rear and no substantial impressionmaterial contacts the user's upper front gums.

Referring next to FIG. 27, a sixth embodiment of a preform 180 for aninterocclusal appliance is shown. The preform 180 has a base 182 or biteplate with a top surface and a bottom surface. An impression material184 is bonded or adhered (such as by molding) onto the top surface ofthe base 182. The base 182 may be formed by injection molding athermoplastic resin into a base mold cavity, and this base 182 is thenplaced into an occlusal appliance mold cavity. The impression material184 may be injected into the occlusal appliance mold cavity over thebase 182. The mold bond between the base 182 and the impression material184 (which later is transformed into the maxillary or mandibularencasement) is required to withstand the lateral and compressivestresses encountered during bruxing or clenching at oral cavitytemperatures.

The base 182 is in the form of a maxillary or mandibular dental arch,having an end portion 186 at one terminus of said arch and another endportion 188 at the other terminus of said arch. Between the two endportions 186, 188 is a central portion 190 of the base. Preferably, andthe bottom surface (or occlusal face) of the base is generally planarThe buccal sidewalls of the base 182 may slope slightly downwardly fromthe rear of the preform 180 to the labial face at the central portion190. The thickness of the base material may range from about 0.25 mm toabout 4.0 mm.

The impression material 184 generally covers the top surface of the base182. The impression material 184 is formed to have a first outerupstanding ridge 192 (buccal peripheral wall) and a second outerupstanding ridge 194 (buccal peripheral wall), and an inner upstandingridge 196 (lingual peripheral wall). The upper surfaces of theimpression material between the outer upstanding ridges 192, 194 (buccalperipheral walls) and the inner upstanding ridge 196 (lingual peripheralwall) define tooth receiving portions 198, 200. Tooth receiving portions198, 200 may alternately be called pilot channels configured tofacilitate placement of the user's maxillary or mandibular molars at anoptimal position during and throughout self-fitting of the appliance. Afront ledge 202 formed in the impression material 184 at the centerportion 190 is sloped downwardly. For an appliance to be worn over upperteeth, this slope may be at an angle complementary to the angle at whichupper or maxillary front incisor and/or bicuspid teeth generally aredisposed in an adult mouth. The impression material 184 is transformedinto either a maxillary molar encasement or mandibular molar encasementduring self-fitting of the interocclusal appliance.

A heat and fit self-fitting procedure may be used to form aninterocclusal appliance of the sixth embodiment of the invention fromthe preform 180 of FIG. 27 for wearing over the maxillary (upper) teeth.First, the preform 180 is heated, such as by immersion in boiling waterfor 30 seconds to 2 minutes to soften the impression material 184. Thepreform 180 is heated to a temperature that can be comfortably withstoodby oral tissue, such as a temperature between about 110° F. and 140° F.The preform 180 is then inserted into the mouth (oral cavity) with theupper molars (maxillary occlusal surfaces) seated in the teeth receivingportions 198, 200 of the preform 180. Biting pressure is applied and themaxillary molars are impressed into the impression material 184. Theimpression material flows over and around the molars to adapt to theshape of the surfaces of the maxillary molars. Concurrently, theimpression material 184 at the ledge 202 and the impression materialforming the central portion of the inner ridge 196 may be shaped toconform to a portion of the user's palate behind the front teeth. Uponcooling, the impression material 184 is transformed into a reusableflexible maxillary molar encasement within the appliance. No impressionmaterial 184 or only an insubstantial amount of impression materialcontacts the front surface of the user's front teeth. No substantialimpression material extends between the front teeth and the user's upperlip. No impression material and no base material extend below the lowertips of the user's front teeth. (Alternatively, the base material mayextend below the lower tips of the user's front teeth for extrasupport.) As so fitted, the interocclusal appliance of this sixthembodiment leaves a more natural gap between a user's front incisorteeth. Such gap or air channel permits the user to breathe morenaturally through his or her mouth during sleep.

Referring next to FIG. 28, a seventh embodiment of the inventioncomprises a preform 210 having a base 212 or bite plate with a topsurface and a bottom surface. An impression material 214 is bonded oradhered onto the top surface of the base 212. The base 212 has two endportions 216, 218 that are joined by a center portion 220 formed betweenthe two end portions 216, 218. The bottom surfaces (or occlusal faces)of the end portions 216, 218 of the base are generally planar. Thebuccal sidewalls of the end portions of the base 212 may slopedownwardly from the rear of the preform 220 toward the front of thepreform.

Because the center portion 220 has a shorter width in cross-section thanthe end portions 216, 218. The preform 220 has ability to flex,comparable to the embodiment shown in FIG. 1. The preform 220 may beflexed from a first position where end portions 216, 218 are spacedapart a first distance to a second position where end portions 216, 218are spaced apart a second distance, where the second distance is greaterthan the first distance.

In the embodiment in FIG. 28, the impression material 214 generallycovers the top surface of the base 212. The impression material 214 isformed to have a first outer upstanding ridge 222 and a second outerupstanding ridge 224, and an inner upstanding ridge 226 (lingualperipheral wall) in the form of an arc. A raised step 227 is formed atthe center portion of the upstanding ridge 226. The upper surfaces ofthe impression material between the outer upstanding ridges 222, 224(buccal peripheral walls) and the inner upstanding ridge 226 (lingualperipheral wall) define tooth receiving portions 228, 230. Toothreceiving portions 228, 230 may alternately be called pilot channelsconfigured to facilitate placement of the user's maxillary molars (ormandibular molars) at an optimal position during and throughoutself-fitting of the appliance. The impression material 214 at the teethreceiving portions 228, 230 is transformed into a maxillary molarencasement (or alternatively mandibular molar encasement) duringself-fitting of the interocclusal appliance of this seventh embodiment.

The impression material 214 of the preform 220 also is formed to have adownwardly sloped front face 232 at the central portion 220. Thisdownwardly sloped front face 232 helps to register and seat the preformin the user's mouth behind the front teeth. The downwardly sloped frontface 232 may be shaped to conform to a portion of the user's palatebehind the front teeth during the self-fitting procedure. Just as withthe embodiment of FIGS. 1-4, if a heat and fit self-fitting procedure isused, the preform 220 is heated, such as by immersion in hot water, tosoften the impression material 214 before the preform 220 is insertedover the teeth of the user's maxillary arch to transform into amaxillary molar encasement. Alternatively, the heated preform 220 may beinserted over the teeth of the user's mandibular arch to transform intoa mandibular molar encasement.

A finished appliance according to this seventh embodiment is not shownin the Figures. However, just as with the first embodiment shown in FIG.4, for this seventh embodiment of interocclusal appliance, nosubstantial impression material 214 contacts the front surface of theuser's front teeth. No substantial impression material extends betweenthe front teeth and the user's upper lip. No impression material and nobase material extend below the lower tip of the user's front teeth. Thefront teeth are not encased in impression material, and thus theinterocclusal appliance is more comfortable to wear.

An eighth embodiment of the invention shown in FIGS. 29 to 32 and 35comprises a preform 240 having a base 242 or bite plate in the form of adental arch and having a top surface and a bottom surface. An impressionmaterial 244 is bonded or adhered onto the top surface of the base 242.The base 242 has two end portions 241, 243 that are joined by a centerportion 249 formed between the two end portions 241, 243. The bottomsurfaces (or occlusal faces) of the end portions 241, 243 of the baseare generally planar and slope downwardly toward the center portion 249of the arch forming the base 242. The buccal sidewalls of the endportions 241, 243 of the base 242 may slope downwardly from the rear ofthe preform 240 toward the front of the preform as shown best in FIG.32.

The impression material 244 generally covers the top surface of the base242. Extra impression material 244 may extend beyond the end portions241, 243 of the base 242. Preferably, about 3.5 g to about 7.0 g ofimpression material are included in the preform according to thisembodiment shown in FIG. 29 to ensure sufficient molar encasement. Theimpression material 244 is formed to have a first outer upstanding ridge246 and a second outer upstanding ridge 247, and an inner upstandingridge 248 (lingual peripheral wall) in the form of an arc. Theimpression material 244 follows the slope contour of the base 242, andthe top surface of the outer upstanding ridges 246, 247 may slope at thesame angle or at a different angle from the slope of the base 242. Atthe front ends 256, 258 of the outer upstanding ridges 246, 247 theslope of the top surface of the impression material may change to asteeper angle than at the end or mid point of such ridges. In addition,at the center portion of the arc of the base 242, the top surface of theimpression material 244 more steeply slopes downwardly forming a ledge250. Such slanted front ledge 250 facilitates fitting the preform intothe user's mouth when self-fitting to form an interocclusal appliance asexplained in more detail below.

The impression material ledge 250 terminates at the apex portion of thearch of the base 242. Thus, a portion of the top surface of the base 242at the apex portion of the arc or arch is exposed without impressionmaterial 244 thereon. At that apex portion of the arc, a ridge 260extends slightly upwardly from the top surface of the base 242. Suchridge 260 facilitates seating the preform 240 into a user's mouth whenfitting the interocclusal appliance as explained in more detail below.While illustrated as a continuous upstanding ridge in FIGS. 29-32, aguide to facilitate seating the preform 240 into a user's mouthalternatively may be a single raised portion or a series of raisedportions, such as nibs or burrs, or a discontinuous ridge, such as aseries of raised dashes.

The ridge 260 and the surface of the base 242 have a greater surfacearea exposed without impression material in the space adjacent to thefront ends 256, 258 of the outer upstanding ridges 246, 247. Such basetop surface without impression material facilitates positioning thepreform 240 into a user's mouth and conforming the impression materialto the teeth and palate surfaces when fitting the interocclusalappliance as explained in more detail below.

The upper surfaces of the impression material between the outerupstanding ridges 246, 247 (buccal peripheral walls) and the innerupstanding ridge 248 (lingual peripheral wall) define tooth receivingportions 252, 264. Tooth receiving portions 262, 254 may alternately becalled pilot channels configured to facilitate placement of the user'smaxillary molars at an optimal position during and throughoutself-fitting of the appliance over the maxillary teeth. The impressionmaterial 244 at the teeth receiving portions 252, 254 is transformedinto a maxillary molar encasement during self-fitting of theinterocclusal appliance of this eighth embodiment.

The fitting procedure in some respects is similar to that for otherembodiments having a base or base plate and associated impressionmaterial described above. Just as with the embodiment of FIGS. 1-4, fora heat and fit procedure, the preform 240 is heated, such as byimmersion in hot water, to soften the impression material 244 before thepreform 240 is inserted over the teeth of the user's maxillary arch totransform into a maxillary molar encasement. The combination of theledge 250 and the ridge 260 assist a user to install the preform 240 fora conforming fit. The user seats the tips of his incisor teeth on thebase surface adjacent to the ridge 260 and between the ridge 260 of thebase 242 and the ledge 260 of impression material 244. The ridge 260guides the user to maintain at least a portion of the base top surfaceunder the tips of the incisor teeth. The ledge 250 assists with shapingthe softened impression material 244 so as to better conform to thespace behind the user's front incisors and to contact the user's palatebehind the user's front incisors. The spaces adjacent to the front ends256, 258 of the ridges provide additional room for cuspid and/orbicuspid teeth, which have a greater tip diameter/depth than doincisors. As such, the spaces adjacent to the front ends 256, 258 permitthe tips of cuspids/bicuspids to seat on the top surface of the base 242during the fitting procedure.

A finished appliance according to this eighth embodiment (FIGS. 29-32and 35) is not shown in the Figures. However, just as with the firstembodiment shown in FIG. 4, for this eighth embodiment of theinterocclusal appliance, no substantial impression material 244 contactsthe front surface of the user's front teeth. No substantial impressionmaterial extends between the front teeth and the user's upper lip.However, the lower tips of the user's front teeth are supported by thetop surface of the base material 242 and are appropriately positionedthere with guidance from the ridge 260. Thus, a minor height of basematerial (e.g., the ridge 260) contacts the front surfaces of the user'sfront teeth. The molars are encased in impression material, but thefront teeth are not so encased. Thus the interocclusal appliance is morecomfortable to wear.

Referring next to FIG. 36, an alternate embodiment of the preform 240Aof FIGS. 29 to 32 is shown. In this alternate embodiment, the base 242Ahas been modified to incorporate a series of bores 266 extending throughthe material forming the base. Such bores 266 provide air channels forgreater breathing comfort when the interocclusal appliance is worn overthe teeth. Bores 266 are shown as circular in FIG. 36, but may also beconfigured as slots or channels or any suitable alternativecross-sectional shape. Bores 266 are shown extending through the middleof the thickness of the base 242A, but also might be formed at thebottom surface of the base.

FIGS. 33 to 35 illustrate alternate cross sections for molar receivingportions of preforms to form interocclusal appliances according thepresent invention. Referring first to FIG. 35, which is across-sectional view of the preform 240 of FIG. 31, the impressionmaterial 244 is held in contact with the top surface of the base 242between and over the side walls 241 formed in such base 242. In such anembodiment, a pilot channel is formed between the side walls 247, 248 toassist a user to seat the molars within the preform during fitting.Alternatively, referring to FIG. 33, a preform may be formed withoutpilot channels, such that the impression material 272 contacts the topsurface of the base 270. As another alternative, the preform may have abase 280 with a concavely dished top surface and the impression material282 may be held in contact with that dished surface. The outer edges ofthe dished top surface of the base 282 help to seat the molars withinthe interocclusal appliance formed from such preform.

To accommodate fitting persons with larger jaws whose rear teeth extendbeyond the rear edges of the end portions of the base, excess impressionmaterial may be bonded at, near or in the receiving portions of the baseof the two component preforms. Such excess impression material will flowbeyond the end portions of the base, to encase or engage the user's rearteeth. In this way, a preform having a base with a shorter dental archmay be fitted to a user with a larger jaw. Hence, a smaller size preformmay be offered that can still accommodate those users with larger jawsizes. Unlike some current commercial products that have a larger baseor tray that must be cut to shorten to fit users with smaller jaw sizes,the present invention can be formed with a commensurately smaller base.No cutting is needed. The impression material then can expand out of thebase to fit users with larger jaws.

Many of the embodiments according to the invention described hereininclude a base in combination with an impression material, wherein thebase is formed from a polymeric material that has a higher softeningpoint temperature than does the impression material bonded or adheredthereto. Alternatively, it is within the scope of the invention hereinto form a self-fitted interocclusal appliance with a single polymermaterial that has a softening point sufficient to be fitted to a user'smaxillary or mandibular teeth and upon setting has a hardness sufficientto protect the user's teeth during bruxing or clenching events when theappliance is worn. For example, as shown in FIG. 12A, a preform 280 isformed with a single polymeric material (or mixture of materials)without a distinct separate base and impression material. While similarto the preform 80 of FIGS. 9-12, the preform 280 in FIG. 12A includes alingual peripheral wall 282 but lacks buccal peripheral walls.

Suitable polymer materials that may be selected for a one-componentpreform include thermoset and thermoplastic polymers (or mixturesthereof wherein the polymers (or mixtures) have a Shore A hardness of atleast 20. For example, alpha polyolefins mixed with ethylene vinylacetate copolymers having 30% by weight or more of vinyl acetate forincreased hardness may meet the rigorous requirements for a onecomponent preform.

The invention has been illustrated by detailed description and examplesof the preferred embodiments. Various changes in form and detail will bewithin the skill of persons skilled in the art. Therefore, the inventionmust be measured by the claims and not by the description of theexamples or the preferred embodiments.

1. An interocclusal appliance for fitting over maxillary teeth of auser, comprising: a polymeric material formed in a configurationgenerally of a dental arch having a bottom plan surface and having twoend portions and a central portion together forming said dental arch,wherein said end portions each define receiving portions for receivingat least one maxillary molar, and said central portion shaped so as tobe disposed behind at least some of the user's front teeth; and whereinsaid interocclusal appliance formed from said polymeric material lackssubstantial material in front of the user's front teeth.
 2. Theinterocclusal appliance of claim 1, wherein the end portions of thedental arch may be spaced further from one another by flexing thepolymeric material.
 3. The interocclusal appliance of claim 1, whereinupon heating the polymeric material to a temperature that is above itsVicat softening temperature, the receiving portions may be molded intocavities for receiving at least one mnaxillary molar, and said centralportion may be shaped to conform to a portion of the user's palatebehind one or more of the user's front teeth.
 4. The interocclusalappliance of claim 1, wherein the receiving portions releaseably fitover two or more of the user's maxillary molars, and once fitted, theappliance is maintained in fitted position in the user's mouth over suchmaxillary molars until the user elects to remove said appliance from themouth.
 5. The interocclusal appliance of claim 1, wherein the centralportion forms a preformed upstanding bridge or arch between the endportions.
 6. The interocclusal appliance of claim 1, wherein a slantedledge is formed at the central portion.
 7. The interocclusal applianceof claim 1, wherein a front tooth guide extends generally upwardly froma top surface of the dental arch at the central portion.
 8. Theinterocclusal appliance of claim 7, wherein the front tooth guidecomprises a continuous arcuate ridge.
 9. The interocclusal appliance ofclaim 7, wherein the front tooth guide comprises one or moreprojections.
 10. The interocclusal appliance of claim 1, wherein aninner upstanding ridge extends generally upwardly from a top surface ofthe dental arch.
 11. The interocclusal appliance of claim 1, wherein anouter upstanding ridge extends generally upwardly from a top surface ofthe dental arch at least one end portion.
 12. The interocclusalappliance of claim 10, wherein an outer upstanding ridge extendsgenerally upwardly from a top surface of the dental arch at least oneend portion.
 13. The interocclusal appliance of claim 1, wherein thepolymeric material has a Shore A hardness of at least about
 20. 14. Theinterocclusal appliance of claim 1, wherein the polymeric materialcomprises a material selected from the group consisting of: ethylenemethyl acrylate (EMA) copolymers, ethylene vinyl acetate (EVA)copolymers, acrylics, high density polyethylenes (HDPE), styrenics(IMPS), acrylonitrile-butadiene-styrene (ABS) copolymers,poly(methylmethacrylates) (IM-PMMA), alpha-polyolefins, polypropylene,polycarbonate, polycaprolactam, polycaprolactone, polyurethanes,polyesters, and mixtures thereof.
 15. The interocclusal appliance ofclaim 1, wherein the polymeric material comprises a resin or mixture ofresins further incorporating a one or more types of larger particles ornanoparticles.
 16. The interocclusal appliance of claim 15, wherein theparticles are selected from the group consisting of pigments, colorants,plated clays, carbon fibrils, carbon nanotubes, and mixtures thereof.17. An interocclusal appliance for fitting over maxillary or mandibularteeth of a user, comprising: a preform comprising a base and animpression material, wherein the base has a bottom plan surface in aconfiguration of a dental arch having two end portions and a centralportion together forming said dental arch, and said base has a topsurface; wherein the impression material is bonded to the top surface ofsaid base, with said impression material defining receiving portions inthe end portions of the base for receiving one or more molars at eachend portion; wherein said impression material comprises a polymericmaterial that has a Vicat softening temperature, and said base comprisesa polymeric material, and upon heating the preform to a temperature thatis above the Vicat softening temperature of the impression materialpolymeric material, the receiving portions may be molded into cavitiesfor receiving at least one molar; and wherein said interocclusalappliance formed from said preform lacks substantial polymeric materialin front of the user's front teeth.
 18. The interocclusal appliance ofclaim 17, further comprising an inner upstanding ridge extendinggenerally upwardly from the top surface of the dental arch.
 19. Theinterocclusal appliance of claim 18, wherein the upstanding inner ridgeof impression material extends from right side end portion to left sideend portion along the entire lingual surface of the preform.
 20. Theinterocclusal appliance of claim 17, further comprising an outerupstanding ridge extending generally upwardly from the top surface ofthe dental arch at least one end portion.
 21. The interocclusalappliance of claim 17, wherein the top surface of the base is eithersubstantially flat, slanted, or concavely dished at least one endportion.
 22. The interocclusal appliance of claim 17, further comprisinga slanted ledge of impression material formed at the central portion.23. The interocclusal appliance of claim 17, wherein a front tooth guideextends generally upwardly from a top surface of the dental arch at thecentral portion.
 24. The interocclusal appliance of claim 23, whereinthe front tooth guide comprises a continuous arcuate ridge.
 25. Theinterocclusal appliance of claim 23, wherein the front tooth guidecomprises one or more projections.
 26. The interocclusal appliance ofclaim 17, further comprising an upstanding arch of impression materialthat bridges between the receiving portions in the preform.
 27. Theinterocclusal appliance of claim 17, wherein the appliance lackspolymeric material in contact with the tips of at least some of theuser's front teeth.
 28. The interocclusal appliance of claim 17, whereinthe appliance has polymeric material in contact with at least some ofthe tips of the user's front teeth.
 29. The interocclusal appliance ofclaim 17, wherein an air flow passage is formed within or under thecentral portion of the base.
 30. The interocclusal appliance of claim17, wherein at least one air flow passage is formed in the base.
 31. Theinterocclusal appliance of claim 17, wherein the end portions of thebase are spaced apart a first distance and may be separated to be spacedapart a second distance greater than the first distance by flexing thepreform.
 32. The interocclusal appliance of claim 31, wherein the seconddistance is greater than the first distance in the range of about 2 toabout 35 mm.
 33. The interocclusal appliance of claim 17, wherein thebase defines at least one notch between one end portion and the centralportion.
 34. The interocclusal appliance of claim 17, wherein anupstanding arch of impression material bridges between the receivingportions in the preform, and at least one notch is formed at one end ofthe arch.
 35. The interocclusal appliance of claim 17, wherein thereceiving portions in the end portions of the base are shaped to receiveone or more maxillary molars.
 36. The interocclusal appliance of claim17, wherein excess impression material is bonded at or near thereceiving portions in the end portions of the base such that uponfitting the appliance said excess impression material may engage theuser's rear teeth that extend beyond the end portions of the base. 37.The interocclusal appliance of claim 36, wherein the excess impressionmaterial engaging the rear teeth extends beyond the bottom plan surfaceof the base.
 38. The interocclusal appliance of claim 17, wherein thepolymeric material forming the base has a Shore A hardness of at leastabout
 20. 39. The interocclusal appliance of claim 17, wherein the basecomprises a polymeric material selected from the group consisting of:ethylene methyl acrylate (EMA) copolymers, acrylics, high densitypolyethylenes (HDPE), styrenics (IMPS), acrylonitrile-butadiene-styrene(ABS) copolymers, poly(methylmethacrylates) (IM-PMMA), polypropylene,polycarbonate, polycaprolactam, polycaprolactone, polyurethanes,polyesters, polypropylene-ethylene propylene diene monomer (PP/EPDM),thermoplastic vulcanizates (TPV), acrylic rubber TPV,styrene-butadiene-styrene (SBS) TPV, low density polyethylene (LDPE),polyvinylchoride (PVC), very low density polyethylene (VLDPE),styrene-butadiene copolymer (SBC) elastomer compounds,styrene-butadiene-styrene (SBS) linear block copolymers,styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB) n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),polyethersulfone (PES), glass reinforced polyethersulfone,polyphenylsulfone (PPSU), styrene-acrylonitrile (SAN),acrylic-styrene-methyimethacrylate coploymers (NAS),polydimethylsilicone (PDMS), polyurea, silicone-polyurea, segmentedpolyurethane (SPU), perfluoroelastomer (FFKM), perfluoroelastomer(FEPM), chlorosulfonated polyethylene rubber, fluoroelastomer, siliconeroom temperature vulcanizate (RTV), cast polyurethane, chloroprenerubber, hydrogenated nitrile-butadiene rubber (HNBR), nitrile rubber,silicone rubber, perfuoroelastomer compounds (FFKT), and mixturesthereof.
 40. The interocclusal appliance of claim 17, wherein theimpression material comprises a polymeric material selected from thegroup consisting of: ethylene methyl acrylate (EMA) copolymers, ethylenevinyl acetate (EVA) copolymers, acrylics, high density polyethylenes(HDPE), styrenics (IMPS), acrylonitrile-butadiene-styrene (ABS)copolymers, poly(methylmethacrylates) (IM-PMMA), alpha-polyolefins,polypropylene-ethylene propylene diene monomer (PP/EPDM) thermoplasticvulcanizates (TPV), acrylic rubber TPV, styrene-butadiene-styrene (S BS)TPV, low density polyethylene (LDPE), polyvinylchoride (PVC),styrene-butadiene copolymer (SBC) elastomer compounds,styrene-butadiene-styrene (SBS) linear block copolymers,styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),styrene-acrylonitrile (SAN), polydimethylsilicone (PDMS), polyurea,silicone-polyurea, segmented polyurethanes (SPU), perfluoroelastomer(FFKM), perfluoroelastomer (FEPM), chlorosulfonated polyethylene rubber,fluoroelastomer, silicone room temperature vulcanizate (RTV), castpolyurethane, chloroprene rubber, hydrogenated nitrile-butadiene rubber(HNBR), nitrile rubber, silicone rubber, perfuoroelastomer compounds(FFKT), and mixtures thereof.
 41. The interocclusal appliance of claim17, wherein impression material comprises from 0 to 85% by weight of anethylene vinyl acetate copolymer having up to about 30% by weight vinylacetate or mixture of such copolymers, and from 15 to 100% by weight ofone or more alpha-polyolefins.
 42. The interocclusal appliance of claim41, wherein the ethylene vinyl acetate copolymer or mixture of suchcopolymers has less than about 10% by weight vinyl acetate.
 43. Theinterocclusal appliance of claim 17, wherein the polymeric materialforming the base has a Shore A hardness of at least 20 and theimpression material comprises an ethylene vinyl acetate copolymer ormixture of said copolymers having from about 0 to about 30% by weightvinyl acetate.
 44. The interocclusal appliance of claim 17, wherein thepolymeric material of the base further incorporates one or more types oflarger particles or nanoparticles.
 45. The interocclusal appliance ofclaim 17, wherein the polymeric material of the impression materialfurther incorporates one or more types of larger particles ornanoparticles.
 46. The interocclusal appliance of claim 44, wherein thenanoparticles are selected from the group consisting of pigments,colorants, plated clays, carbon fibrils, carbon nanotubes, and mixturesthereof.
 47. The interocclusal appliance of claim 45, wherein thenanoparticles are selected from the group consisting of pigments,colorants, plated clays, carbon fibrils, carbon nanotubes, and mixturesthereof.
 48. An interocclusal appliance for fitting over maxillary teethof a user, comprising: a preform comprising a first base, a second baseand an impression material, wherein the first and second bases each havebottom surfaces, and have top plan surfaces in a configuration forreceiving two or more maxillary molars, with the first base spaced apartfrom the second base; wherein first and second portions of theimpression material are bonded to top surfaces of said first base andsaid second base, with said portions of impression material definingreceiving portions for receiving maxillary molars, and wherein a thirdportion of said impression material forms a bridge between the firstbase and the second base; and wherein said impression material comprisesa polymeric material that has a Vicat softening temperature, and saidbases comprise a polymeric material, and upon heating the preform to atemperature that is above the Vicat softening temperature of theimpression material, the receiving portions may be molded into cavitiesfor receiving the maxillary molars, and said bridge of impressionmaterial may be shaped to conform to a portion of a user's palate. 49.The interocclusal appliance of claim 48, wherein said interocclusalappliance lacks material in contact with front surfaces of the user'sfront teeth.
 50. The interocclusal appliance of claim 48, wherein saidfirst portion of impression material forms a channel with upstandingside ridges to help the user position the preform to receive maxillarymolars.
 51. The interocclusal appliance of claim 50, wherein said secondportion of impression material forms a channel with upstanding sideridges to help the user position the preform to receive maxillarymolars.
 52. The interocclusal appliance of claim 48, wherein excessimpression material is bonded at or near the receiving portions in theend portion of each base such that upon fitting the appliance saidexcess impression material may engage the user's rear teeth that extendbeyond the end portions of the bases.
 53. The interocclusal appliance ofclaim 52, wherein the excess impression material engaging the rear teethextends beyond the bottom surfaces of each base.
 54. The interocclusalappliance of claim 48, wherein the polymeric material forming the baseshas a Shore A hardness of at least about
 20. 55. The interocclusalappliance of claim 48, wherein the bases comprise a polymeric materialselected from the group consisting of: ethylene methyl acrylate (EMA)copolymers, acrylics, high density polyethylenes (HDPE), styrenics(IMPS), acrylonitrile-butadiene-styrene (ABS) copolymers,poly(methylmethacrylates) (IM-PMMA), polypropylene, polycarbonate,polycaprolactam, polycaprolactone, polyurethanes, polyesters,polypropylene-ethylene propylene diene monomer (PP/EPDM), thermoplasticvulcanizates (TPV), acrylic rubber TPV, styrene-butadiene-styrene (SBS)TPV, low density polyethylene (LDPE), polyvinylchoride (PVC), very lowdensity polyethylene (VLDPE), styrene-butadiene copolymer (SBC)elastomer compounds, styrene-butadiene-styrene (SBS) linear blockcopolymers, styrene-isoprene-styrene (SIS) linear block copolymersstyrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),polyethersulfone (P ES), glass reinforced polyethersulfone,polyphenylsulfone (PPSU), styrene-acrylonitrile (SAN),acrylic-styrene-methylmethacrylate coploymers (NAS),polydimethylsilicone (PDMS), polyurea, silicone-polyurea, segmentedpolyurethane (SPU), perfluoroelastomer (FFKM), perfluoroelastomer(FEPM), chlorosulfonated polyethylene rubber, fluoroelastomer, siliconeroom temperature vulcanizate (RTV), cast polyurethane, chloroprenerubber, hydrogenated nitrile-butadiene rubber (HNBR), nitrile rubber,silicone rubber, perfuoroelastomer compounds (FFKT), and mixturesthereof.
 56. The interocclusal appliance of claim 48, wherein theimpression material comprises a polymeric material selected from thegroup consisting of: ethylene methyl acrylate (EMA) copolymers, ethylenevinyl acetate (EVA) copolymers, acrylics, high density polyethylenes(HDPE), styrenics (IMPS), acrylonitrile-butadiene-styrene (ABS)copolymers, poly(methylmethacrylates) (IM-PMMA), alpha-polyolefins,polypropylene-ethylene propylene diene monomer (PP/EPDM) thermoplasticvulcanizates (TPV), acrylic rubber TPV, styrene-butadiene-styrene (SBS)TPV, low density polyethylene (LDPE), polyvinylchoride (PVC),styrene-butadiene copolymer (SBC) elastomer compounds,styrene-butadiene-styrene (SBS) linear block copolymers,styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),styrene-acrylonitrile (SAN), polydimethylsilicone (PDMS), polyurea,silicone-polyurea, segmented polyurethanes (SPU), perfluoroelastomer(FFKM), perfluoroelastomer (FEPM), chlorosulfonated polyethylene rubber,fluoroelastomer, silicone room temperature vulcanizate (RTV), castpolyurethane, chloroprene rubber, hydrogenated nitrile-butadiene rubber(HNBR), nitrile rubber, silicone rubber, perfuoroelastomer compounds(FFKT), and mixtures thereof.
 57. The interocclusal appliance of claim48, wherein impression material comprises from 0 to 85% by weight of anethylene vinyl acetate copolymer having up to about 30% by weight vinylacetate or mixture of such copolymers, and from 15 to 100% by weight ofone or more alpha-polyolefins.
 58. The interocclusal appliance of claim57, wherein the ethylene vinyl acetate copolymer or mixture of suchcopolymers has less than about 10% by weight vinyl acetate.
 59. Theinterocclusal appliance of claim 48, wherein the polymeric material ofthe base further incorporates one or more types of larger particles ornanoparticles.
 60. The interocclusal appliance of claim 48, wherein thepolymeric material of the impression material further incorporates oneor more types of larger particles or nanoparticles.
 61. Theinterocclusal appliance of claim 59, wherein the nanoparticles areselected from the group consisting of pigments, colorants, plated clays,carbon fibrils, carbon nanotubes, and mixtures thereof.
 62. Theinterocclusal appliance of claim 60, wherein the nanoparticles areselected from the group consisting of pigments, colorants, plated clays,carbon fibrils, carbon nanotubes, and mixtures thereof.
 63. Aninterocclusal appliance for fitting over maxillary incisor teeth of auser, comprising: a preform comprising a base and an impressionmaterial, wherein the base has a bottom plan surface in a configurationof a partial dental arch; wherein the impression material is bonded tothe top surface of said base, with said impression material defining areceiving portion for receiving two or more maxillary front teeth;wherein said impression material comprises a polymeric material that hasa Vicat softening temperature, and said base comprises a polymericmaterial, and upon heating the preform to a temperature that is abovethe Vicat softening temperature of the impression material, thereceiving portion may be molded into cavities for receiving themaxillary front teeth, and a portion of said impression material may beshaped to conform to a portion of the user's palate behind the user'sfront teeth; and wherein said interocclusal appliance lacks impressionmaterial in contact with the user's maxillary molars.
 64. Theinterocclusal appliance of claim 63, further comprising an upstandinglabial ridge extending from the base.
 65. The interocclusal appliance ofclaim 63, wherein the receiving portion has a sufficient span to receiveat least six maxillary front teeth.
 66. The interocclusal appliance ofclaim 63, wherein a portion of the impression material may be shaped incontact with front surfaces of the user's incisors.
 67. Theinterocclusal appliance of claim 63, wherein the polymeric materialforming the base has a Shore A hardness of at least about
 20. 68. Theinterocclusal appliance of claim 63, wherein the base comprises apolymeric material selected from the group consisting of: ethylenemethyl acrylate (EMA) copolymers, acrylics, high density polyethylenes(HOPE), styrenics (IMPS)(acrylonitrile-butadiene-styrene (ABS)copolymers, poly(methylmethacrylates) (IM-PMMA), polypropylene,polycarbonate, polycaprolactam, polycaprolactone, polyurethanes,polyesters, polypropylene-ethylene propylene diene monomer (PP/EPDM),thermoplastic vulcanizates (TPV), acrylic rubber TPV,styrene-butadiene-styrene (SBS) TPV, low density polyethylene (LDPE),polyvinylchoride (PVC), very low density polyethylene (VLDPE),styrene-butadiene copolymer (SBC) elastomer compounds,styrene-butadiene-styrene (SBS) linear block copolymers,styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SF RS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),polyethersulfone (PES), glass reinforced polyethersulfone,polyphenylsulfone (PPSU), styrene acrylonitrile (SAN),acrylic-styrene-methylmethacrylate coploymers (NAS),polydimethylsilicone (PDMS), polyurea, silicone-polyurea, segmentedpolyurethane (SPU), perfluoroelastomer (FFKM), perfluoroelastomer(FEPM), chlorosulfonated polyethylene rubber, fluoroelastomer, siliconeroom temperature vulcanizate (RTV), cast polyurethane, chloroprenerubber, hydrogenated nitrile-butadiene rubber (HNBR), nitrile rubber,silicone rubber, perfuoroelastomer compounds (FFKT), and mixturesthereof.
 69. The interocclusal appliance of claim 63, wherein theimpression material comprises a polymeric material selected from thegroup consisting of: ethylene methyl acrylate (EMA) copolymers, ethylenevinyl acetate (EVA) copolymers, acrylics, high density polyethylenes(HDPE), styrenics (IMPS), acrylonitrile-butadiene-styrene (ABS)copolymers, poly(methylmethacrylates) (IM-PMMA), alpha-polyolefins,polypropylene-ethylene propylene diene monomer (PP/EPDM) thermoplasticvulcanizates (TPV), acrylic rubber TPV, styrene-butadiene-styrene (SBS)TPV, low density polyethylene (LDPE), polyvinylchoride (PVC),styrene-butadiene copolymer (SBC) elastomer compounds,styrene-butadiene-styrene (SBS) linear block copolymers,styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),styrene-acrylonitrile (SAN), polydimethylsilicone (PDMS), polyurea,silicone-polyurea, segmented polyurethanes (SPU), perfluoroelastomer(FFKM), perfluoroelastomer (FEPM), chlorosulfonated polyethylene rubber,fluoroelastomer, silicone room temperature vulcanizate (RTV), castpolyurethane, chloroprene rubber, hydrogenated nitrile-butadiene rubber(HNBR), nitrile rubber, silicone rubber, perfuoroelastomer compounds(FFKT), and mixtures thereof.
 70. The interocclusal appliance of claim63, wherein impression material comprises from 0 to 85% by weight of anethylene vinyl acetate copolymer having up to about 30% by weight vinylacetate or mixture of such copolymers, and from 15 to 100% by weight ofone or more alpha-polyolefins.
 71. The interocclusal appliance of claim70, wherein the ethylene vinyl acetate copolymer or mixture of suchcopolymers has less than about 10% by weight vinyl acetate.
 72. Theinterocclusal appliance of claim 63, wherein the polymeric material ofthe base further incorporates one or more types of larger particles ornanoparticles.
 73. The interocclusal appliance of claim 63, wherein thepolymeric material of the impression material further incorporates oneor more types of larger particles or nanoparticles.
 74. A method offabricating an interocclusal appliance for alleviating adverse effectsof bruxing or clenching events, comprising: (a) forming a one componentappliance from a polymeric material having a Shore A hardness of atleast
 20. 75. The method of claim 74, wherein the polymeric material isformed in a configuration generally of a dental arch having a bottomplan surface and having two end portions and a central portion togetherforming said dental arch, wherein said end portions each definereceiving portions for receiving at least one maxillary molar, and saidcentral portion shaped so as to be disposed behind at least some of theuser's front teeth; and wherein said interocclusal appliance formed fromsaid polymeric material lacks substantial material in front of theuser's front teeth.
 76. The method of claim 75, further comprising: (b)heating the polymeric material to a temperature that is above its Vicatsoftening temperature; and (c) installing the appliance into a user'smouth so that when the user applies biting pressure thereon thereceiving portions may be molded into cavities for receiving at leastone maxillary molar.
 77. The method of claim 76, further comprising: (d)indexing the appliance within the user's mouth during the installingstep by locating front teeth in front of a slanted ledge formed at thecentral portion of the dental arch.
 78. The method of claim 76, furthercomprising: (d) indexing the appliance within the user's mouth duringthe installing step by locating front teeth substantially adjacent to afront tooth guide extending generally upwardly from a top surface of thedental arch at the central portion.
 79. The method of claim 74, whereinthe polymeric material is selected from the group consisting of:ethylene methyl acrylate (EMA) copolymers, acrylics, high densitypolyethylenes (HDPE), styrenics (IMPS), acrylonitrile-butadiene-styrene(ABS) copolymers, poly(methylmethacrylates) (IM-PMMA), polypropylene,polypolycarbonate, polycaprolactam, polycaprolactone, polyurethanes,polyesters, alpha-polyolefins, and mixtures thereof.
 80. The method ofclaim 74, wherein the polymeric material contains one or more largerparticles or nanoparticles.
 81. A method of fabricating an interocclusalappliance for alleviating adverse effects of bruxing or clenchingevents, comprising: (a) forming an appliance base from a polymericmaterial having a Shore A hardness of at least about 20; and (b) bondingto the base an impression material of a polymeric material compositioncomprising from 0 to about 85% by weight of an ethylene vinyl acetatecopolymer or mixture of such copolymers having up to approximately 30%by weight vinyl acetate, and from about 15 to 100% by weight ofalpha-polyolefins.
 82. The method of claim 81, wherein the impressionmaterial further incorporates one or more larger particles ornanoparticles.
 83. The method of claim 82, wherein the particles areselected from the group consisting of pigments, colorants, plated clays,carbon fibrils, carbon nanotubes, and mixtures thereof.
 84. The methodof claim 81, wherein the base further incorporates one or more largerparticles or nanoparticles.
 85. The method of claim 84, wherein theparticles are selected from the group consisting of pigments, colorants,plated clays, carbon fibrils, carbon nanotubes, and mixtures thereof.86. The method of claim 81, wherein the polymeric material of theappliance base is selected from the group consisting of: ethylene methylacrylate (EMA) copolymers, acrylics, high density polyethylenes (HDPE),styrenics (IMPS), acrylonitrile-butadiene-styrene (ABS) copolymers,poly(methylmethacrylates) (IM-PMMA), polypropylene, polycarbonate,polycaprolactam, polycaprolactone, polyurethanes, polyesters,polypropylene-ethylene propylene diene monomer (PP/EPDM) thermoplasticvulcanizates (TPV), acrylic rubber TPV, styrene-butadiene-styrene (SBS)TPV, low density polyethylene (LDPE), polyvinylchoride (PVC), very lowdensity polyethylene (VLDPE), styrene-butadiene copolymer (SBC)elastomer compounds, styrene-butadiene-styrene (SBS) linear blockcopolymers, styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers, styrene-co-ethylenebutene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),polyethersulfone (PES), glass reinforced polyethersulfone,polyphenylsulfone (PPSU), styrene-acrylonitrile (SAN),acrylic-styrene-methylmethacrylate coploymers (NAS),polydimethylsilicone (PDMS), polyurea, silicone-polyurea, segmentedpolyurethane (SPU), perfluoroelastomer (FFKM), perfluoroelastomer(FEPM), chlorosulfonated polyethylene rubber, fluoroelastomer, siliconeroom temperature vulcanizate (RTV), cast polyurethane, chloroprenerubber, hydrogenated nitrile-butadiene rubber (HNBR), nitrile rubber,silicone rubber, perfuoroelastomer compounds (FFKT), and mixturesthereof.
 87. The method of claim 81, wherein the impression materialcomprises no more than about 10% by weight vinyl acetate.
 88. The methodof claim 81, wherein the impression material comprises up to about 25%by weight vinyl acetate.
 89. The method of claim 81, wherein theimpression material comprises one or more alpha-polyolefins withoutethylene vinyl acetate.
 90. The method of claim 81, wherein the Shore Ahardness of the base material is between about 20 and about
 80. 91. Themethod of claim 81, wherein the Shore A hardness of the base material isat least about
 80. 92. The method of claim 81, wherein the base isformed in a configuration generally of a dental arch having a bottomplan surface and having two end portions and a central portion togetherforming said dental arch, and said central portion shaped so as to bedisposed behind at least some of the user's front teeth, and wherein theimpression material is bonded to the top surface of said base, with saidimpression material defining receiving portions in the end portions ofthe base for receiving one or more molars at each end portion; andwherein said appliance formed from said base and impression materiallacks substantial polymeric material in front of the user's front teeth.93. The method of claim 92, further comprising: (b) heating theimpression material to a temperature that is above its Vicat softeningtemperature; and (c) installing the appliance into a user's mouth sothat when the user applies biting pressure thereon the receivingportions may be molded into cavities for receiving the maxillary molars.94. The method of claim 93, further comprising: (d) indexing theappliance within the user's mouth during the installing step by locatingfront teeth in front of a slanted ledge of impression material formed atthe central portion of the dental arch.
 95. The method of claim 93,further comprising: (d) indexing the appliance within the user's mouthduring the installing step by locating front teeth substantiallyadjacent to a front tooth guide extending generally upwardly from a topsurface of the dental arch at the central portion of the base.
 96. Themethod of claim 92, wherein the impression material is present in anamount from about 3.5 g to about 7.0 g of material.
 97. The method ofclaim 92, wherein excess impression material is bonded at or near thereceiving portions in the end portion of the base such that upon fittingthe appliance said excess impression material may engage the user's rearteeth that extend beyond the end portions of the base.
 98. The method ofclaim 97, wherein the excess impression material engaging the rear teethextends beyond the bottom surface of the end portions of the base.
 99. Amethod of fabricating an interocclusal appliance for alleviating adverseeffects of bruxing or clenching events, comprising: (a) forming anappliance base from a polymeric material having a Shore A hardness of atleast about 20; and (b) bonding to the base an impression material of apolymeric material composition comprising an ethylene vinyl acetatecopolymer having from 0 to about 25% by weight vinyl acetate.
 100. Themethod of claim 99, wherein the Shore A hardness is at least about 80.101. The method of claim 99, wherein the impression material is presentin an amount from about 3.5 g to about 7.0 g of material.
 102. A methodof fabricating an interocclusal appliance for alleviating adverseeffects of bruxing or clenching events, comprising: forming at least onecomponent of said appliance from a thermoset or thermoplastic polymerresin composition or combination with less than about 10% by weightvinyl acetate.
 103. The method of claim 102, wherein the composition orcombination further comprises one or more larger particles ornanoparticles.
 104. A method of fabricating an interocclusal appliancefor alleviating adverse effects of bruxing or clenching events,comprising: (a) forming a base from a polymeric material having a ShoreA hardness of at least about 20; and (b) bonding an impression materialto said base, wherein said impression material is a thermoset orthermoplastic polymer resin composition or combination with less thanabout 10% by weight vinyl acetate.
 105. The method of claim 104, whereinthe composition or combination of the impression material furthercomprises one or more larger particles or nanoparticles.
 106. The methodof claim 104, wherein the impression material is present in an amountfrom about 3.5 g to about 7.0 g of material.
 107. A method offabricating an interocclusal appliance for alleviating adverse effectsof bruxing or clenching events, comprising: (a) forming a base; and (b)bonding an impression material to said base, wherein said impressionmaterial is an alpha-polyolefin or combination of alpha-polyolefins.108. The method of claim 107, wherein the impression material furthercomprises one or more larger particles or nanoparticles.
 109. The methodof claim 107, wherein the impression material further comprises lessthan 10% by weight vinyl acetate.
 110. The method of claim 107, whereinthe impression material is present in an amount from about 3.5 g toabout 7.0 g of material.
 111. A method of fabricating an interocclusalappliance for alleviating adverse effects of bruxing or clenchingevents, comprising: (a) forming a base from a polymeric material havinga Shore A hardness between about 20 to below 80; and (b) bonding to thebase an impression material from a resin comprising an ethylene acetatecopolymer having up to about 30% by weight vinyl acetate.
 112. A methodof fabricating an interocclusal appliance for alleviating adverseeffects of bruxing or clenching events, comprising: (a) forming anappliance base from a polymeric material having a Shore A hardness of atleast about 20; and (b) bonding to the base an impression material,wherein the base is formed in a configuration generally of a dental archhaving a bottom plan surface and having two end portions and a centralportion together forming said dental arch, and said central portionshaped so as to be disposed behind at least some of the user's frontteeth, and wherein the impression material is bonded to the top surfaceof said base, with said impression material defining receiving portionsin the end portions of the base for receiving one or more molars at eachend portion; and wherein said appliance formed from said base andimpression material lacks substantial polymeric material in front of theuser's front teeth.
 113. The method of claim 112, wherein the polymericmaterial of the appliance base is selected from the group consisting of:ethylene methyl acrylate (EMA) copolymers, acrylics, high densitypolyethylenes (HDPE), styrenics (IMPS), acrylonitrile-butadiene-styrene(ABS) copolymers, poly(methylmethacrylates) (IM-PM MA), polypropylene,polycarbonate, polycaprolactam, polycaprolactone, polyurethanes,polyesters, polypropylene-ethylene propylene diene monomer (PP/EPDM),thermoplastic vulcanizates (TPV), acrylic rubber TPV,styrene-butadiene-styrene (SBS) TPV, low density polyethylene (LDPE),polyvinylchoride (PVC), very low density polyethylene (VLDPE),styrene-butadiene copolymer (SBC) elastomer compounds,styrene-butadiene-styrene (SBS) linear block copolymers,styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene-propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),polyethersulfone (PES), glass reinforced polyethersulfone,polyphenylsulfone (PPSU), styrene-acrylonitrile (SAN),acrylic-styrene-methylmethacrylate coploymers (NAS),polydimethylsilicone (PDMS), polyurea, silicone-polyurea, segmentedpolyurethane (SPU), perfluoroelastomer (FFKM), perfluoroelastomer(FEPM), chlorosulfonated polyethylene rubber, fluoroelastomer, siliconeroom temperature vulcanizate (RTV), cast polyurethane, chloroprenerubber, hydrogenated nitrile-butadiene rubber (HNBR), nitrile rubber,silicone rubber, perfuoroelastomer compounds (FFKT), and mixturesthereof.
 114. The method of claim 112, wherein the impression materialcomprises a polymeric material selected from the group consisting of:ethylene methyl acrylate (EMA) copolymers, ethylene vinyl acetate (EVA)copolymers, acrylics, high density polyethylenes (HDPE), styrenics(IMPS), acrylonitrile-butadiene-styrene (ABS) copolymers,poly(methylmethacrylates) (IM-PMMA), alpha-polyolefins,polypropylene-ethylene propylene diene monomer (PP/EPDM) thermoplasticvulcanizates (TPV), acrylic rubber TPV, styrene-butadiene-styrene (SBS)TPV, low density polyethylene (LDPE), polyvinylchoride (PVC),styrene-butadiene copolymer (SBC) elastomer compounds,styrene-butadiene-styrene (SBS) linear block copolymers,styrene-isoprene-styrene (SIS) linear block copolymers,styrene-butadiene (SB)n branched copolymers,styrene-co-ethylene-butene-styrene (SEBS) linear block copolymers,styrene-co-ethylene propylene (SEP) diblock copolymers,styrene-co-ethylene-ethylene-propylene-styrene (SEEPS) copolymers,mineral reinforced thermoplastic ethylene-styrene (TES/SEBS),styrene-acrylonitrile (SAN), polydimethylsilicone (PDMS), polyurea,silicone-polyurea, segmented polyurethanes (SPU), perfluoroelastomer(FFKM), perfluoroelastomer (FEPM), chlorosulfonated polyethylene rubber,fluoroelastomer, silicone room temperature vulcanizate (RTV), castpolyurethane, chloroprene rubber, hydrogenated nitril-butadiene rubber(HNBR), nitrile rubber, silicone rubber, perfuoroelastomer compounds(FFKT), and mixtures thereof.
 115. The method of claim 112, furthercomprising: (b) heating the impression material to a temperature that isabove its Vicat softening temperature; and (c) Installing the applianceinto a user's mouth so that when the user applies biting pressurethereon the receiving portions may be molded into cavities for receivingthe maxillary molars.
 116. A method for monitoring wear of aninterocclusal appliance, comprising: (a) providing the interocclusalappliance to a user, where such interocclusal appliance is formed withat least one polymeric material having a Shore A hardness of at leastabout 20 into which is incorporated one or more particles to cause theat least one polymeric material to be opaque, translucent or colored toa first degree substantially throughout; (b) observing a change in theopacity, translucency or coloration of a portion of the polymericmaterial.
 117. The method of claim 116, wherein the opacity,translucency or coloration of the portion of the polymeric materialchanges to a second degree as compared to the first degree after anamount of polymeric material is removed from a surface of theinterocclusal appliance.